Searching nationwide and international in libraries

GBV
WorldCat
KVK
Karlsruhe Virtual Catalog
Book search interface for more than hundreds of million books and serials in library and book trade catalogs worldwide.
German Journal Database (ZDB)
In the ZDB, you will find serial titles, newspapers, databases, yearbooks etc., in short, everything that was and is being published periodically in printed or electronic form and that is available in German and Austrian libraries. On the European level access to digitized newspapers will be constantly expanded.